From owner-freebsd-fs  Thu Sep 21  7:10: 7 2000
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From: Stephen Byan <Stephen.Byan@quantum.com>
To: "'Marius Bendiksen'" <mbendiks@eunet.no>,
	Stephen Byan <Stephen.Byan@quantum.com>
Cc: "'Soren Schmidt'" <sos@freebsd.dk>, fs@FreeBSD.ORG,
	sos@FreeBSD.ORG, freeBSD-scsi@FreeBSD.ORG
Subject: RE: disable write caching with softupdates?
Date: Thu, 21 Sep 2000 07:08:37 -0700
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Marius Bendiksen [mailto:mbendiks@eunet.no] wrote:

> > Contrast this 10% performance hit versus what you get when=20
> you disable
> > caching entirely.
>=20
> I think you will see that on some drives, this may have a greater
> performance impact than not caching at all.

Perhaps S=F8ren will be kind enough to run the experiment? I'd be =
interested
in analyzing cases in ATA drives where flushing delivers worse =
performance
than disabling cache.

Regards,
-Steve


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